News from CREAL
Several studies, mostly among female nurses, have suggested that night shift work is a risk factor for breast cancer. One of the main mechanisms underlying this association is the light induced suppression of melatonin, a hormone that protects against cancer that is normally produced at night while we sleep. Other mechanisms include circadian disruption (disruption of daily biological rhythms) and sleep deprivation.
Even so, there are still some doubts about the validity of some of the existing studies. It is remarkable that 4 systematic reviews and meta-analyses were published in 2013 with inconclusive results.
Researchers at CREAL, a research centre of ISGlobal alliance, Manolis Kogevinas and Kyriaki Papantoniou, comment in an editorial published in the journal Occupational Environmental Medicine on the Grundy et al. paper published in the same issue of this journal. They reflect on the need of future research in this field in order to confirm the effects of night shift work and circadian disruption in breast cancer and other tumors.
Papantoniou K, Kogevinas M. Shift work and breast cancer: do we need more evidence and what should this be? Occup Environ Med 2013.